石灰浆液高压静电雾化脱硫试验及机理研究

Lime Slurry Wet Flue Gas Desulfurization Based on High-voltage Electrostatic Atomization Technology

将高压静电雾化技术引入湿钙法烟气脱硫中,通过不同方案和不同工况下的脱硫试验比较,得到雾滴与烟气接触方式、烟气中SO2质量浓度、荷电电压以及钙与硫的物质的量比(nCa/nS)等对烟气脱硫的影响,综合分析了高压静电引起脱硫增益的机理.结果表明:石灰浆液荷电能够使雾滴细化、均匀化,增加传质面积和接触机会,同时改变雾滴表面特性,增大传质速率,使脱硫率得到不同程度的提高,且脱硫率随荷电电压的增加而提高;脱硫效果与气液接触方式有关,在试验设定的nCa/nS范围内,浆液流量较大时同向并流的脱硫率增幅明显高于逆向流动时,而浆液流量较低时采用逆向流动荷电脱硫更有利.

Based on high-voltage electrostatic atomization technology, experimental tests on lime slurry desulfurization process were carried out via various schemes under different working conditions, during which factors influencing the flue gas desulfurization were analyzed, such as the contact style between droplet and flue gas, the mass concentration of SO2, the value of charge voltage and the ratio of nca/ns etc. , while the desulfurization enhancement mechanism by the atomization technology studied. Results show that the electric charging of lime slurry may atomize and uniform the droplets, enhance the mass transfer, improve the surface property of droplets, and therefore raise the desulfurization efficiency in dif- ferent degrees, which rises with growing charge voltage. Moreover, the desulfurization efficiency has some relationships with the gas-liquid contact pattern. Within the range of experimental settings of nca/ns ratio, at relatively high lime slurry flux, the growing rate of desulphurization efficiency in the co-current flow condition is obviously higher than in the counter-current flow condition, while, at relatively low lime slurry flux, the counter-current flow condition is of favorableness.